The invention relates to an arrangement for the segmentation, classification and approximation of lines which are defined by a series of points, and whereby each point is determined by its coordinates and a directional angle.
The performance of the visual sensors for the position recognition of workpieces presently commercially available is generally not sufficient for use in flexible production situations in order to permit an economical and technically expedient use of such apparatus.
The sensors presently commercially available image the three dimensional scene which contains the workpieces into a binary image since the workpiece to be recognized stands out as a white area from the black background, or vice versa. This areal pattern, describing the silouette of the workpiece, is evaluated or analyzed with comparatively simple algorithms (for example, center of gravity calculation for position determination, determination of the axis of inertia, or "polar check" for rotational position determination). This type of evaluation or analysis assumes that various workpieces do not contact one another or overlap, but that, on the other hand, a workpiece will also not fall into several areas through the binary processing. Accordingly, for the recognition of non-isolated workpieces, the point of departure must be the gray scale value image (picture half-tone) in which edges are visible.
For the evaluation of picture halftone images, numerous algorithms exist which, however, generally are extremely computationally bound and normally do not enter into consideration for use in manufacturing automation on account of the required apparatus and time expense.